An American journalist has received a friendly visit from an anti-terrorism squad, after she googled "pressure cookers" and "backpack".

In March Google reported that the FBI monitors the internet for potential terrorist activity.

Michele Catalano said she had researched pressure cookers and her husband was looking for a backpack, a combination of terms that raises flags in the wake of bombings at the Boston Marathon on April 15 that killed three people and injured more than 260.

In a blog post describing the incident, Catalano wrote: Mostly I felt a great sense of anxiety. This is where we are at. Where you have no expectation of privacy. Where trying to learn how to cook some lentils could possibly land you on a watch list. Where you have to watch every little thing you do because someone else is watching every little thing you do."

Catalano said the agents told her husband that "they do this about 100 times a week. And that 99 of those visits turn out to be nothing."

After the initial scare, Catalano made light of the situation.

Pro tip: don't do a search for pressure cookers right after your spouse does a search for backpacks if you don't want the FBI at your door.